src/lxc/macro.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #ifndef __LXC_MACRO_H
   4 #define __LXC_MACRO_H
   5
   6 #ifndef _GNU_SOURCE
   7 #define _GNU_SOURCE 1
   8 #endif
   9 #define __STDC_FORMAT_MACROS
  10 #include <asm/types.h>
  11 #include <limits.h>
  12 #include <linux/if_link.h>
  13 #include <linux/loop.h>
  14 #include <linux/netlink.h>
  15 #include <linux/rtnetlink.h>
  16 #include <linux/types.h>
  17 #include <stdint.h>
  18 #include <string.h>
  19 #include <sys/mount.h>
  20 #include <sys/socket.h>
  21 #include <sys/un.h>
  22 #include <unistd.h>
  23
  24 #ifndef PATH_MAX
  25 #define PATH_MAX 4096
  26 #endif
  27
  28 #ifndef MAX_GRBUF_SIZE
  29 #define MAX_GRBUF_SIZE 2097152
  30 #endif
  31
  32 #define INT64_FMT "%" PRId64
  33
  34 /* Define __S_ISTYPE if missing from the C library. */
  35 #ifndef __S_ISTYPE
  36 #define __S_ISTYPE(mode, mask) (((mode)&S_IFMT) == (mask))
  37 #endif
  38
  39 /* capabilities */
  40 #ifndef CAP_SETGID
  41 #define CAP_SETGID 6
  42 #endif
  43
  44 #ifndef CAP_SETUID
  45 #define CAP_SETUID 7
  46 #endif
  47
  48 #ifndef CAP_SYS_ADMIN
  49 #define CAP_SYS_ADMIN 21
  50 #endif
  51
  52 #ifndef CAP_SETFCAP
  53 #define CAP_SETFCAP 31
  54 #endif
  55
  56 #ifndef CAP_MAC_OVERRIDE
  57 #define CAP_MAC_OVERRIDE 32
  58 #endif
  59
  60 #ifndef CAP_MAC_ADMIN
  61 #define CAP_MAC_ADMIN 33
  62 #endif
  63
  64 /* prctl */
  65 #ifndef PR_CAPBSET_READ
  66 #define PR_CAPBSET_READ 23
  67 #endif
  68
  69 #ifndef PR_CAPBSET_DROP
  70 #define PR_CAPBSET_DROP 24
  71 #endif
  72
  73 /* Control the ambient capability set */
  74 #ifndef PR_CAP_AMBIENT
  75 #define PR_CAP_AMBIENT 47
  76 #endif
  77
  78 #ifndef PR_CAP_AMBIENT_IS_SET
  79 #define PR_CAP_AMBIENT_IS_SET 1
  80 #endif
  81
  82 #ifndef PR_CAP_AMBIENT_RAISE
  83 #define PR_CAP_AMBIENT_RAISE 2
  84 #endif
  85
  86 #ifndef PR_CAP_AMBIENT_LOWER
  87 #define PR_CAP_AMBIENT_LOWER 3
  88 #endif
  89
  90 #ifndef PR_CAP_AMBIENT_CLEAR_ALL
  91 #define PR_CAP_AMBIENT_CLEAR_ALL 4
  92 #endif
  93
  94 #ifndef PR_SET_NO_NEW_PRIVS
  95 #define PR_SET_NO_NEW_PRIVS 38
  96 #endif
  97
  98 #ifndef PR_GET_NO_NEW_PRIVS
  99 #define PR_GET_NO_NEW_PRIVS 39
 100 #endif
 101
 102 /* filesystem magic values */
 103 #ifndef CGROUP_SUPER_MAGIC
 104 #define CGROUP_SUPER_MAGIC 0x27e0eb
 105 #endif
 106
 107 #ifndef CGROUP2_SUPER_MAGIC
 108 #define CGROUP2_SUPER_MAGIC 0x63677270
 109 #endif
 110
 111 #ifndef NSFS_MAGIC
 112 #define NSFS_MAGIC 0x6e736673
 113 #endif
 114
 115 /* current overlayfs */
 116 #ifndef OVERLAY_SUPER_MAGIC
 117 #define OVERLAY_SUPER_MAGIC 0x794c7630
 118 #endif
 119
 120 /* legacy overlayfs */
 121 #ifndef OVERLAYFS_SUPER_MAGIC
 122 #define OVERLAYFS_SUPER_MAGIC 0x794c764f
 123 #endif
 124
 125 /* Calculate the number of chars needed to represent a given integer as a C
 126  * string. Include room for '-' to indicate negative numbers and the \0 byte.
 127  * This is based on systemd.
 128  */
 129 #define INTTYPE_TO_STRLEN(type)                   \
 130         (2 + (sizeof(type) <= 1                   \
 131                   ? 3                             \
 132                   : sizeof(type) <= 2             \
 133                         ? 5                       \
 134                         : sizeof(type) <= 4       \
 135                               ? 10                \
 136                               : sizeof(type) <= 8 \
 137                                     ? 20          \
 138                                     : sizeof(int[-2 * (sizeof(type) > 8)])))
 139
 140 /* Useful macros */
 141 #define LXC_LINELEN 4096
 142 #define LXC_IDMAPLEN 4096
 143 #define LXC_MAX_BUFFER 4096
 144 #define LXC_NAMESPACE_NAME_MAX 256
 145
 146 /* /proc/       =    6
 147  *                +
 148  * <pid-as-str> =   INTTYPE_TO_STRLEN(pid_t)
 149  *                +
 150  * /fd/         =    4
 151  *                +
 152  * <fd-as-str>  =   INTTYPE_TO_STRLEN(int)
 153  *                +
 154  * \0           =    1
 155  */
 156 #define LXC_PROC_PID_FD_LEN \
 157         (6 + INTTYPE_TO_STRLEN(pid_t) + 4 + INTTYPE_TO_STRLEN(int) + 1)
 158
 159 /* /proc/        = 6
 160  *               +
 161  * <pid-as-str>  = INTTYPE_TO_STRLEN(pid_t)
 162  *               +
 163  * /status       = 7
 164  *               +
 165  * \0            = 1
 166  */
 167 #define LXC_PROC_STATUS_LEN (6 + INTTYPE_TO_STRLEN(pid_t) + 7 + 1)
 168
 169 /* /proc/        = 6
 170  *               +
 171  * <pid-as-str>  = INTTYPE_TO_STRLEN(pid_t)
 172  *               +
 173  * /attr/        = 6
 174  *               +
 175  * /current      = 8
 176  *               +
 177  * \0            = 1
 178  */
 179 #define LXC_LSMATTRLEN (6 + INTTYPE_TO_STRLEN(pid_t) + 6 + 8 + 1)
 180
 181 #define LXC_CMD_DATA_MAX (PATH_MAX * 2)
 182
 183 /* loop devices */
 184 #ifndef LO_FLAGS_AUTOCLEAR
 185 #define LO_FLAGS_AUTOCLEAR 4
 186 #endif
 187
 188 #ifndef LOOP_CTL_GET_FREE
 189 #define LOOP_CTL_GET_FREE 0x4C82
 190 #endif
 191
 192 /* memfd_create() */
 193 #ifndef MFD_CLOEXEC
 194 #define MFD_CLOEXEC 0x0001U
 195 #endif
 196
 197 #ifndef MFD_ALLOW_SEALING
 198 #define MFD_ALLOW_SEALING 0x0002U
 199 #endif
 200
 201 /**
 202  * BUILD_BUG_ON - break compile if a condition is true.
 203  * @condition: the condition which the compiler should know is false.
 204  *
 205  * If you have some code which relies on certain constants being equal, or
 206  * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
 207  * detect if someone changes it.
 208  *
 209  * The implementation uses gcc's reluctance to create a negative array, but
 210  * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
 211  * to inline functions).  So as a fallback we use the optimizer; if it can't
 212  * prove the condition is false, it will cause a link error on the undefined
 213  * "__build_bug_on_failed".  This error message can be harder to track down
 214  * though, hence the two different methods.
 215  */
 216 #ifndef __OPTIMIZE__
 217 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2 * !!(condition)]))
 218 #else
 219 extern int __build_bug_on_failed;
 220 #define BUILD_BUG_ON(condition)                              \
 221         do {                                                 \
 222                 ((void)sizeof(char[1 - 2 * !!(condition)])); \
 223                 if (condition)                               \
 224                         __build_bug_on_failed = 1;           \
 225         } while (0)
 226 #endif
 227
 228 #define lxc_iterate_parts(__iterator, __splitme, __separators)                  \
 229         for (char *__p = NULL, *__it = strtok_r(__splitme, __separators, &__p); \
 230              (__iterator = __it);                                               \
 231              __iterator = __it = strtok_r(NULL, __separators, &__p))
 232
 233 #define prctl_arg(x) ((unsigned long)x)
 234
 235 /* networking */
 236 #ifndef NETLINK_GET_STRICT_CHK
 237 #define NETLINK_GET_STRICT_CHK 12
 238 #endif
 239
 240 #ifndef SOL_NETLINK
 241 #define SOL_NETLINK 270
 242 #endif
 243
 244 #ifndef IFLA_LINKMODE
 245 #define IFLA_LINKMODE 17
 246 #endif
 247
 248 #ifndef IFLA_LINKINFO
 249 #define IFLA_LINKINFO 18
 250 #endif
 251
 252 #ifndef IFLA_NET_NS_PID
 253 #define IFLA_NET_NS_PID 19
 254 #endif
 255
 256 #ifndef IFLA_NET_NS_FD
 257 #define IFLA_NET_NS_FD 28
 258 #endif
 259
 260 #ifndef IFLA_INFO_KIND
 261 #define IFLA_INFO_KIND 1
 262 #endif
 263
 264 #ifndef IFLA_VLAN_ID
 265 #define IFLA_VLAN_ID 1
 266 #endif
 267
 268 #ifndef IFLA_INFO_DATA
 269 #define IFLA_INFO_DATA 2
 270 #endif
 271
 272 #ifndef VETH_INFO_PEER
 273 #define VETH_INFO_PEER 1
 274 #endif
 275
 276 #ifndef VETH_MODE_BRIDGE
 277 #define VETH_MODE_BRIDGE 1
 278 #endif
 279
 280 #ifndef VETH_MODE_ROUTER
 281 #define VETH_MODE_ROUTER 2
 282 #endif
 283
 284 #ifndef IFLA_MACVLAN_MODE
 285 #define IFLA_MACVLAN_MODE 1
 286 #endif
 287
 288 #ifndef IFLA_IPVLAN_MODE
 289 #define IFLA_IPVLAN_MODE 1
 290 #endif
 291
 292 #ifndef IFLA_IPVLAN_ISOLATION
 293 #define IFLA_IPVLAN_ISOLATION 2
 294 #endif
 295
 296 #ifndef IFLA_NEW_NETNSID
 297 #define IFLA_NEW_NETNSID 45
 298 #endif
 299
 300 #ifdef IFLA_IF_NETNSID
 301 #ifndef IFLA_TARGET_NETNSID
 302 #define IFLA_TARGET_NETNSID = IFLA_IF_NETNSID
 303 #endif
 304 #else
 305 #define IFLA_IF_NETNSID 46
 306 #define IFLA_TARGET_NETNSID 46
 307 #endif
 308
 309 #ifndef IFA_TARGET_NETNSID
 310 #define IFA_TARGET_NETNSID 10
 311 #endif
 312
 313 #ifndef IFLA_STATS
 314 #define IFLA_STATS 7
 315 #endif
 316
 317 #ifndef IFLA_STATS64
 318 #define IFLA_STATS64 23
 319 #endif
 320
 321 #ifndef RTM_NEWNSID
 322 #define RTM_NEWNSID 88
 323 #endif
 324
 325 #ifndef RTM_GETNSID
 326 #define RTM_GETNSID 90
 327 #endif
 328
 329 #ifndef NLMSG_ERROR
 330 #define NLMSG_ERROR 0x2
 331 #endif
 332
 333 #ifndef MACVLAN_MODE_PRIVATE
 334 #define MACVLAN_MODE_PRIVATE 1
 335 #endif
 336
 337 #ifndef MACVLAN_MODE_VEPA
 338 #define MACVLAN_MODE_VEPA 2
 339 #endif
 340
 341 #ifndef MACVLAN_MODE_BRIDGE
 342 #define MACVLAN_MODE_BRIDGE 4
 343 #endif
 344
 345 #ifndef MACVLAN_MODE_PASSTHRU
 346 #define MACVLAN_MODE_PASSTHRU 8
 347 #endif
 348
 349 #ifndef IPVLAN_MODE_L2
 350 #define IPVLAN_MODE_L2 0
 351 #endif
 352
 353 #ifndef IPVLAN_MODE_L3
 354 #define IPVLAN_MODE_L3 1
 355 #endif
 356
 357 #ifndef IPVLAN_MODE_L3S
 358 #define IPVLAN_MODE_L3S 2
 359 #endif
 360
 361 #ifndef IPVLAN_ISOLATION_BRIDGE
 362 #define IPVLAN_ISOLATION_BRIDGE 0
 363 #endif
 364
 365 #ifndef IPVLAN_ISOLATION_PRIVATE
 366 #define IPVLAN_ISOLATION_PRIVATE 1
 367 #endif
 368
 369 #ifndef IPVLAN_ISOLATION_VEPA
 370 #define IPVLAN_ISOLATION_VEPA 2
 371 #endif
 372
 373 /* Attributes of RTM_NEWNSID/RTM_GETNSID messages */
 374 enum {
 375         __LXC_NETNSA_NONE,
 376 #define __LXC_NETNSA_NSID_NOT_ASSIGNED -1
 377         __LXC_NETNSA_NSID,
 378         __LXC_NETNSA_PID,
 379         __LXC_NETNSA_FD,
 380         __LXC_NETNSA_MAX,
 381 };
 382
 383 /* Length of abstract unix domain socket socket address. */
 384 #define LXC_AUDS_ADDR_LEN sizeof(((struct sockaddr_un *)0)->sun_path)
 385
 386 /* mount */
 387 #ifndef MS_PRIVATE
 388 #define MS_PRIVATE (1<<18)
 389 #endif
 390
 391 #ifndef MS_SLAVE
 392 #define MS_SLAVE (1 << 19)
 393 #endif
 394
 395 #ifndef MS_LAZYTIME
 396 #define MS_LAZYTIME (1<<25)
 397 #endif
 398
 399 #ifndef MS_REC
 400 #define MS_REC 16384
 401 #endif
 402
 403 /* open */
 404 #ifndef O_PATH
 405 #define O_PATH      010000000
 406 #endif
 407
 408 #ifndef O_NOFOLLOW
 409 #define O_NOFOLLOW  00400000
 410 #endif
 411
 412 /* sockets */
 413 #ifndef SOCK_CLOEXEC
 414 #define SOCK_CLOEXEC 02000000
 415 #endif
 416
 417 /* pointer conversion macros */
 418 #define PTR_TO_INT(p) ((int)((intptr_t)(p)))
 419 #define INT_TO_PTR(u) ((void *)((intptr_t)(u)))
 420
 421 #define PTR_TO_PID(p) ((pid_t)((intptr_t)(p)))
 422 #define PID_TO_PTR(u) ((void *)((intptr_t)(u)))
 423
 424 #define PTR_TO_UINT64(p) ((uint64_t)((intptr_t)(p)))
 425
 426 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 427 #define PTR_TO_USHORT(p) ((unsigned short)((uintptr_t)(p)))
 428
 429 #define LXC_INVALID_UID ((uid_t)-1)
 430 #define LXC_INVALID_GID ((gid_t)-1)
 431
 432 #define STRLITERALLEN(x) (sizeof(""x"") - 1)
 433 #define STRARRAYLEN(x) (sizeof(x) - 1)
 434
 435 /* Maximum number of bytes sendfile() is able to send in one go. */
 436 #define LXC_SENDFILE_MAX 0x7ffff000
 437
 438 #define move_ptr(ptr)                                 \
 439         ({                                            \
 440                 typeof(ptr) __internal_ptr__ = (ptr); \
 441                 (ptr) = NULL;                         \
 442                 __internal_ptr__;                     \
 443         })
 444
 445 #define move_fd(fd)                         \
 446         ({                                  \
 447                 int __internal_fd__ = (fd); \
 448                 (fd) = -EBADF;              \
 449                 __internal_fd__;            \
 450         })
 451
 452 #define ret_set_errno(__ret__, __errno__)                     \
 453         ({                                                    \
 454                 typeof(__ret__) __internal_ret__ = (__ret__); \
 455                 errno = (__errno__);                          \
 456                 __internal_ret__;                             \
 457         })
 458
 459 #define ret_errno(__errno__)         \
 460         ({                           \
 461                 errno = (__errno__); \
 462                 -(__errno__);        \
 463         })
 464
 465 #define free_move_ptr(a, b)          \
 466         ({                           \
 467                 free(a);             \
 468                 (a) = move_ptr((b)); \
 469         })
 470
 471 /* Container's specific file/directory names */
 472 #define LXC_CONFIG_FNAME      "config"
 473 #define LXC_PARTIAL_FNAME     "partial"
 474 #define LXC_ROOTFS_DNAME      "rootfs"
 475 #define LXC_TIMESTAMP_FNAME   "ts"
 476 #define LXC_COMMENT_FNAME     "comment"
 477
 478 #define ARRAY_SIZE(x)                                                        \
 479         (__builtin_choose_expr(!__builtin_types_compatible_p(typeof(x),      \
 480                                                              typeof(&*(x))), \
 481                                sizeof(x) / sizeof((x)[0]), ((void)0)))
 482
 483 #ifndef TIOCGPTPEER
 484         #if defined __sparc__
 485                 #define TIOCGPTPEER _IO('t', 137)
 486         #else
 487                 #define TIOCGPTPEER _IO('T', 0x41)
 488         #endif
 489 #endif
 490
 491 #endif /* __LXC_MACRO_H */